I like this idea overall, but Apple really ought to include some sort of
check digit mechanism, and publish the formula they picked, so that it's possible to determine with high confidence whether a supplied Apple serial number could actually really be a genuine Apple serial number. (Only Apple would know for sure, of course.) There are all sorts of real world scenarios when businesses, governments, and other organizations need to take accurate inventories and when somebody transposes a digit or otherwise gets the serial number wrong. It'd be darn helpful if all these organizations could know, right away, when they've collected a serial number in their inventory taking that cannot possibly be a genuine Apple serial number.
Also, Apple ought to eliminate all characters from serial numbers that can be easily mistaken for other characters. This generally includes (as examples):
0, O, D, and (probably) Q
5 and S
1, 7, and I
8 and B
U and V
The choice of typeface can matter a lot here -- for example, to distinguish A from R -- but some easy-to-confuse characters ought to be dropped no matter what the typeface. This'll help even Apple's own support teams over the phone, etc., as they deal with consumers. There are still plenty of characters available to allow plenty of serial numbers for billions of products.
Finally (and now that Jony Ive has left!), don't be afraid to make serial numbers easier to read (in larger type) on devices. Apple has got typographic experts, so spend some effort making serial numbers easier to read within whatever (sometimes lame) aesthetic goals Apple is trying to achieve. IBM ThinkPads were pretty damn stylish, and they had big, easy to read serial numbers in easy to inventory places.